Biological versus mechanical prostheses for aortic valve replacement

Objectives: Long-term real-world outcomes are critical for informing decisions about biological (Bio) or mechanical (Mech) prostheses for aortic valve replace-ment, particularly in patients aged between 50 and 65 years. The objective was to compare long-term survival and major adverse cardiac and cardiovascular events (ie, stroke, reoperation, and major bleeding) within this population.Methods: This was a multicenter observational study including all patients aged be-tween 50 and 65 years who underwent an aortic valve replacement because of se-vere isolated aortic stenosis between the years 2000 and 2018. A total of 5215 patients from 27 Spanish hospitals were registered with a follow-up of 15 years. Multivariable analyses, including a 2:1 propensity score matching (1822 Mech and 911 Bio) and competing risks analyses were applied.Results: Bio prostheses were implanted in 19% of patients (n = 992). No significant differences were observed between matched groups in long-term survival (hazard ratio [HR], 1.14; 95% confidence interval [CI], 0.88-1.47; P = .33). Stroke rates were higher for Mech prostheses, but not significant (HR, 0.72; 95% CI, 0.50-1.03; P = .07). Finally, higher rates of major bleeding were found in the Mech group (HR, 0.65; 95% CI, 0.49-0.87; P = .004), whereas reoperation was more frequent among the Bio group (HR, 3.04; 95% CI, 1.80-5.14; P < .001). Bio prostheses increased from 13% in the period from 2000 to 2008 to 24% in 2009 to 2018.Conclusions: Long-term survival was comparable among groups in patients be-tween 50 and 65 years of age. Mech prostheses were associated with a higher risk of major bleeding, whereas Bio prostheses entailed higher reoperation rates. Bio prostheses seem a reasonable choice for patients between 50 and 65 years in Spain. (J Thorac Cardiovasc Surg 2023;165:609-17)